code: def define_graph(self):
      self.data = self.ext_src()
      if self.is_gpu:
          self.data = self.data.gpu()
      return self.one_hot(self.data), self.data
  
imports: from functools import partial
  from nvidia.dali.pipeline import Pipeline
  import nvidia.dali.ops
  import nvidia.dali.types
  from test_utils import check_batch
  from nose_utils import raises
  import numpy
label_desc: Use image node_id 2 for calling the OneHotPipeline obj's underlying member method code with example usage: obj.define_graph() and returns: self,  self